Centuries ago, a Zygon spaceship crash landed in Loch Ness. Now, with their home planet destroyed, the alien creatures plan to take over Earth. Their most powerful weapon is a huge armoured disaur-like creature of terrifying power that they brought to earth as an embryo - the Loch Ness Monster. The Doctor, Sarah and Harry soon discover that the Zygons have ather weapon. They can assume the identity of any human they capture. Who kws which of their friends might really be a Zygon? UNIT faces one of its toughest battles as Broton, Warlord of the Zygons, puts his plan into action and the Loch Ness Monster attacks. This vel is based on a Doctor Who story which was originally broadcast from 30 August to 20 September 1975. This title features the Fourth Doctor as played by Tom Baker, with his companions Sarah Jane Smith and Harry Sullivan and the UNIT organisation commanded by Brigadier Lethbridge-Stewart.
Terrance Dicks worked on scripts for The Avengers as well as other series before becoming Assistant, and later full Script Editor of Doctor Who from 1968. Dicks worked on the entirety of the Jon Pertwee Third Doctor era of the programme, and returned as a writer - scripting Tom Baker's first story as the Fourth Doctor: 'Robot'. His later script writing credits on Doctor Who included the 20th anniversary story 'The Five Doctors'. Terrance Dicks novelised many of the original Doctor Who stories for Target books, and has written original Doctor Who novels for BBC Books. Robert Banks Stewart, the original script writer of 'Loch Ness Monster', has been one of the most prolific and respected writers on British television since the 1960s. Originally a journalist, he moved on to work developing movie scenarios at Pinewood Studios and then into script writing. As well as working as a script editor, he has written extensively for television, including The Avengers, The Sweeney and Doctor Who.